That is interesting - it was my nutritionist who suggested taking the two at alternate times. I specifically asked because I know from studying mineral formation (I'm a geologist), chemistry (they're in the same A-column on the periodic table), etc. that the two ions are highly interchangeable in molecular substances, so presumably just as much so in our bodies. I know a lot less about human physiology, though.

Good question! I am curious about the answer, as I take Carlson's D Drops. I just lick 3 drops (6,000 IU) off of the back of my hand after brushing my teeth---on an empty stomach since I usually skip breakfast. During the summer months I usually only take 1 drop (2,000 IU).

Something to consider if you're trying to get more magnesium into your diet is that Mg and Ca ions can compete with each other. This means if you're taking the Vitamin D with calcium, you might want to do that early in the day, and whatever you're eating or taking for Mg later in the day.

That is interesting - it was my nutritionist who suggested taking the two at alternate times. I specifically asked because I know from studying mineral formation (I'm a geologist), chemistry (they're in the same A-column on the periodic table), etc. that the two ions are highly interchangeable in molecular substances, so presumably just as much so in our bodies. I know a lot less about human physiology, though.

Take them after a fatty meal as everyone has said. It makes more sense to take it during the morning or during the day when our bodies would normally be preforming vitamin D synthesis. No science on that though just some intuition.

I wouldn't be surprised to find out down the road that it doesn't matter whether it's taken with or without fat as long as the diet contains a significant amount of quality fat. The need to take vitamin D with food might also depend on whether you use drops or take pills.

I take it with a fatty meal (don't really have non-fatty meals ever, truth be told) in the morning, but I didn't really notice it affecting sleep when I took it at night. I make sure to eat the 100% dark chocolate and white tea in the morning as well. I think the D3 itself doesn't necessarily affect sleep, but it does have some effect on melatonin production in general, but I think that's just a restoration of the correct level as a whole.

funny to see everyone say that it keeps them awake, cause I just started taking it, and one pill makes me drowsy, 2 will knock me out cold. I am also a natural night owl and prefer to sleep during the day, so I wonder if that has anything to do with it.

I take 5000 IU per day because I'm following a naturopathic protocol for Lyme Disease. I also supplement with a high quality toxin-free fish oil, flax oil, and other healthy oils. My naturopath told me to always take one digestive enzyme capsule with my oils at mealtime. . .

I take 5000 IU per day...and i feel great.And i use it with my breakfast in the morning.I also use Omega 3 Fish oils,and Borage oil.I get all my supplements including these on iherb.Com ,and you can get $10 discount on your first order when you use coupon code ZQL811 at checkouts,and $5 off for every next order!You can save lots of money!Check it out!

I take mine when I remember, and because I don't remember every day, I take more if it's been a couple of days. I also blitz it in the fall trying to build up stocks for the winter. I swear that it's what's been keeping this schoolteacher healthy among the teenager germs over the past few winters.